Abstract
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This paper presents the impact of demand and supply variation due to uncoordinated operation of the photovoltaic and the electric vehicle (EV) uncertainty on voltage stability of low voltage distribution grids. A novel two-stage coordination strategy is proposed to manage demand-generation and voltage profile of the distribution grids where the first stage solves the optimal allocation and sizing of EV charging stations while the latter decides the operation strategy of the EVs. Different case studies are used to demonstrate the impacts of centralized and decentralized EV charging stations on the operation of the distribution grids by considering seasonal effects. The proposed method is applied to a low voltage residential feeder based on an Australian scenario. It is found that the proposed method can reduce a significant amount of unbalance between the demand and generation while improving the overall voltage profile of a distribution grid. It is also found that the decentralized EV charging stations provide better support to the grid than the centralized stations. The power losses and voltage deviations are reduced by 25.73 percent and 0.55 percent, respectively.